Vice-admiral Jonkheer Theodorus Frederik van Capellen, GCMWO, KCB (Nijmegen, 6 September 1762 – Brussels, 15 April 1824) was a Dutch naval officer.

In the Fourth Anglo-Dutch War he distinguished himself in the Dutch defeat of Action of 30 May 1781 between his ship Den Briel and HMS Crescent, and earned an early promotion to captain in 1783.

[2] In any case, Van Capellen was sent to British vice-admiral Mitchell as a parlimentaire on the fateful 30 August 1799, by admiral Story to request a temporary cease-fire.

He also played a leading role in the subsequent council of war aboard the Dutch flagship, during which admiral Story was persuaded to surrender his squadron without a fight to the British.

Van Capellen was tried in absentia and convicted on 16 January 1804 (together with admiral Story and two other officers) of dereliction of duty, cowardice, and disloyalty (though not of treason).